Lethal apparatus



"March 15, 1932. M. MCCURRIE LETHAL APPARATUS Filed Nov. 10, '1930 INVENTOR.

2 MATTHEW M CUBIEI TORNEY Patented Mar. 15, 1932 warren "era MATTHEW MCCURBIE, or raaivcrscoj CALIFORNIA 1 LErrrAL APrARATUs 7 Application filed November 10, 1930; sriai'iivo. 4%521 safety to the operator is obtained. a

An object of my invention is toprovide a new and novel apparatus of the above character in which means is provided for preventing the escape of the gas from the chamber during its operation and which will facilitate an easy and rapid disposition of thegas after it has performed its function. a i

Another object of my invention istoprovide a novel arrangement of ventilating conduits' for lethal apparatus which can" be I changed to exhaust gas from an area external- 7 ly of the apparatus or from within the apparatus by the operation of a single valve. A further object of my invention isto pro- .vide'in conjunction with apparatus ,ofthe above character a novel form of interlocking mechanism between the gas introducing and the ventilating apparatus which willpermit the introduction of gas only when the ven tilating. apparatus is'properly operating.

Other objects and advantages of my: invention will be in part pointed out and in part evident from the followingdescription taken in connection with the accompanying drawings wherein I have shown by way ofillus tration and not of limitation a preferred form of my invention.

In the drawings wherein likenumerals refer to like parts throughout the several views;

Figure 1 is a side elevation of my improved apparatus with a portion broken away.

Figure 2 is a plan view of the apparatus illustrated in Figure 1,

Figure 3 is an endelevation of the ratus shown in Figures '1' and 2, and

Figure 4 is a schematic perspective view conduits and valve therefor;

v v In'the extermination of dogs and cats in a gas chamber of the character contemplated by my inventionitis a comparativelysafe andsimpleoperation to introduce the gas showing the relative positions of the exhaust into a closed chamber, but the later disposition of this gas after the killhas always rii s r 'ram FE been'a problem particularly when the lethal chamber is located in a building where it a Y cannot be opened until the gases have been completelyexhausted therefrom; Q

-' In order to overcome the above difliculties and :providea simple and effective means for, xhausting the gas from such 'a chamber, I

show a suitably located exhaust fan having" a twe-x'vay-inlet conduit and adischarge outlet that communicates'with the atmosphere,

preferably'through the roof of a building.

The two-way inlet'conduit hasa valve which ser c'es to properly connect the suction-side ofthe fan with the nterior of the chamber when the gas is being exhausted therefrom H Y andllwith an arefa adjacent the chamberwhen the latter is in use.

ate a precautionary feature I also show in conjunction with the above conduit valve a. suitable interlocking, mechanism which wi ll prevent an operation of thevalve to close the chamber when the exhaust fan-is not operating andalsoprevent an introduction of gas into the chamber when the valve isvnot properlyset'to'maintain a suction adjacent the door of the chamber. 1 I s r In the accompanying drawings'1O designates a rectangular sealedchamberfor the reception "ofa crate or cagell inwhich the animals'tobe disposedot'may be placed. 'At a the front end of the chamber 10 there is provided a door 12 and projecting outwardly from the chamber over the door 12 there is ahood or cowl arrangement 13. At the rear j side of the chamber 10 there is also shown a o gas container 14 having 'a suitable connecting pipe 15 through which a gas'may be introdu'ced into the chamber10; The pipe 15 is provided withaw'alve 16 for controlling the flow of gas-from the container 14;

' The abo-vedescribed apparatus is all that would be 'requiredto carry out the killing of pests where the apparatus can be properly isolated or located'in some openspacelwhere the attendant can operate same from a safe distance,'--but when itis: desired to operate such an appar'atusjin a buildingit .is necessary}'toprovide additional means for exhausting the chamber and disposing of the gas in a safe and convenient manner after the kill.

This additional apparatus for disposing of the gas and rendering the apparatus safe, as contemplated by my invention, comprises a suitable exhaust fan 17 that discharges through a conduit 18 leading .to the atmosphere, preferably through the roof of a building, and which at its suction side is connected with a two-way or'manifold inlet conduit 19. The fan 17 is driven by a suitable electric motor 20 which is controlled by a switch 21 mounted upon the chamber 10. Extending downwardly from the manifold conduit 19 there is a vertical conduit 22 that communicates with the interioroi" the chamber 10 and a similarly disposed conduit 23 which communicates with the space beneath the hood 13, the connection betweenthe conduit 23 and the space beneath the hood 13 being established by a flaring triangular connection 24 which is perforated at its intake end, as shown at 25 in Figure 3.

I Communicating with the bottom of the chamber 10 and extending externally thereof to a point in line with the manifold conduit 19,1 show a further conduit 26 which communicates with the flaring connection 24 through a suitable valve, as will now appear.

Cooperating with the conduits 22, 23 and 26, I show a single sliding valve element 27 which serves to open and close the last above conduit and to alternately open and close the conduits 22 and 23. Extending from the sliding valve element 27, I show a link 28 which connects with a bell crank 29 pivotally mounted upon the end of the chamber 10. The, bell crank 29 is located adjacent the gas controlling valve 16 and is provided with a downwardly projecting portion 30 which engages an aperture in an operating lever 31 of the valve 16. l

The slidingvalve element 27 also carries a projection 32 that engages a slot 33 and interlocks it with a switch operating lever The lever 34 is connected at its inner end .hrough a slot 35 with the operating handle oi the switch 21 so thatwhen it is pulled out the, switch will be in its on position and when pushed in the switch will be in its oil position.

Associated with the slide valve element 27 there is also provided an interlocking mechanism which connects with a suitable door latch36 for maintaining the door 12 closed when the slide 27 is pulled out to its chamber closing position. This interlocking mechanismmay be of any suitable form. In the drawings it is illustrated as comprising alink 37 .connectingwith the latch 36 and extending up to a lever 38 which is in turn connected through a chain 39 with the slide 27, the chain 39 being passed around a suitably disposedpulley 40. In additionto the latch 36 there is also provided a simple snap lock The bottom of the chamber 10 is shown as raised from the floor and in order to facilitate a rolling of the cage 11 into the chamber I show a suitable incline or ramp 42 which can be lowered by a suitable lever 43 when not in use to permit the closing of the door 12. At the sides of the chamber 10, I also provide oppositely disposed windows 44 and 45 through which the operator can observe the conditions within the chamber.

In describing the operation of my device it will be assumed that the gas to be used is obtained in a steel bottle 14 in which the gas is held under pressure. It will be also assumed that the bott e 14 has been properly connected to the chamber 10 by means or" the pipe 15 and that the valve 16 is in its closed position.

With the apparatus in this condition the operator can safely open the door 12 of the chamber and roll the cage 11 containing the animals into the chamber. The operator will then move the lever 43 and lower the ramp 42 so that the door 12 can be tightl T closed. At this point it should be stated that the door 12 is provided with a suitablesealing gasket so that it will close tightly against the escape of gas. H

After the chamber" has been thus closed, the operator must first pull out the switch operating lever 34 and start the fan 17 before he can open the gas valve 16, however, the normal operation would be to pull out the slide valve 27 and thus by virtue of the interlocking projection 32 he willalso operate, the switclrlev-er 34. This will close the branch conduits 22' and 26 and open the branch conduit 23, and thus connect the suction side of i the fan 17 with the space beneath the hood 13 so as to draw away any gas which might escape through the packing around the door 12.

In pulling out the slide valve 27 the operator will also move the bell crank 29 and withdraw the projecting portion 30 from the operating lever 31 of the valve 16 $0 that the valve can be opened when desired.

After the valve 16 has been opened a suflicient period of time to fully charge the chamber 16, the operator will then observe conditions within the chamber through the windows 44 or 45 when he is satisfied that the kill is complete he will push the valve slide 27 inwardly and again lock the valve 16 in its closed position. During this last operation it will be understood that the switch lever 34'will remain'in its outermost position with the switch 21 on. This is possible because of the slotted or lost motion connection provided by the'projection 32 on the element 27 and the slot 33 on the lever 34.

With the slidingv valve element 27 in this latter position the branch conduit 23 will be closed and the conduits 22-and 26 will be the valve 16 directly into the chambjerflO.

While I have, for the s'akeof 'clearness.

opened so that the suction sideof the fan 17 will be connected directly with the interior of the chamber 10 through the branch conduit 22 and at the same time the conduit 26 will be connected with the flaring conduit 24 and thus a suction will be maintained beneath the hood 13. During this latter operation fresh air will be drawn from beneath the hood 18 through the conduit 26 and into the bottom of the chamber 10 where it will serve to sweep'out all of the deadly gases within the chamber and permit its being opened after a very short lapse of time.

After the gas has been removed from the chamber the operator'can then safely stop the fan 17 by pushing the switch lever 34: to its innermost or ofi' position. 1

By the above arrangement 1t w1ll be seen that I have provided a means for readily disposing of deadly gases in a convenient and safe manner and that the arrangement also provides an additional factor of safety in that during the operation'of the chamber a continuous suction will be maintained where any leakage of. gas is most likely to occur.

In my experiments with various gases I have found that hydrocyanic gas is the most effective for my purpose and while I have illustrated the gas as supplied, under pres sure from a bottle'14,1 desire to have it understood that I may generate the gas in a suitable generator and introduce it through and in order to disclose my'invention so that the same can be readily understood, de

scribed and illustrated specific; devices and arrangements, I desire to have it understood that this invention is not limited to the spe ciiic means disclosed but may be embodied in other ways that will suggest themselves, in view of this broad disclosure, to persons skilled in the art. a

Having thus described my invention, what I claim and desire to secure by Letters Pat ent is 1. In apparatus of the character described,

the combination of a chamber having a door at one end, means for introducing a gas into said chamber, a hood extending outwardly from said chamber over said door, a suction at one end,means for introducinga gas into said chamber, 'ahood extending outwardly from saidchamberover said door, a motor driven suction fan having two inlet conduits,

one connecting with-the interior of said chamber and the other connecting w'ith the space' beneath said hood, a switch for controlling the motor of saidffan', a valve for alternately closingone' orthe other of the" "inlet conduits of said fan, and an interlocking mechanismbetween said valve andsaid switch, whe'reby the conduit between said 'fan and said chamber cannot be closed un til saidfan motoris operating. L Y I Inappa'ratusof thecharacter described,i

the combination of'a' chamber having a door at one end, apparatus for introducinga gas into} said chamber, a motor driven suction fan for exhausting the gas from said-chamher, a switch for controlling the motor of the interior of said chamber, a valve 5 for opennig and closing Silld condu t, and an interlocking mechanism between said valve" and said switch and .gas' introducing appa .ratus forpreventinganintroduction of: gas "into the chamb'erwhen said fan'is not operating and therconduit' valve is open.'.

r 14. in apparatus of the'character described,

the combination cfa chamber having a door atone end, apparatus for introducing'af gas into'said chamber, a suction fanforexhausting. the gas from: said chamber, a conduit vleading-fr'omsaid fan'to the interior of said chamber, it'IVfilVG for opening and closing :said conduit, and an interlocking -mechanism between said valve an'dsaidgas introducing "apparatus for preventing an introduction -of gas into the 'chamberuwhen said conduit valve: is open.- 1 i i .5. In apparatus of the character described, a chamber having atdoor a t-lone end, means for introducing a gas into said chamber, a hood extending outwardly from said chamber over said door, a motor driven suctionfan having an inlet conduit connecting with the space beneath said hood, a switch for controlling the motor of said fan, a valve for opening and closing the inlet conduit of said fan, and an interlocking mechanism between said valve and said switch, whereby as. sa d fangacondrut leadlng from said fan to] ins said fan motor cannot be started until the valve in said conduit is opened.

6. A system of exhaust conduits for lethal apparatus of the character described, comprising. a suction fan having a discharge outlet leading to the atmosphere, an inlet conduit leading to said fan, said inlet conduithaving two branch conduits, one leading into the interior of the chamber and'the other leading to a point beneath a hood projecting over the door of said chamber, a further conduit connecting said last branchfconduit with the bottom of the chamber, and a single valve cooperating with said last conduit and said branch conduits for permitting a suction to be established beneath said hood when in one position and permit a similar suction to be maintained from beneath said hood and an exhaust of the chamber when in another position.

7 Inapparatus of the character described, the combination of a chamber having a door atone end, apparatus for introducing a gas into said chamber, a motor driven suction "fan for exhausting the gas from said chamber,

a lock for maintaining said door closed when said chamber contains gas, a conduit leading from the atmosphere and through said fan 5 to the interior of said chamber, a valve for opening and closing said conduit, and an interlocking mechanism between said valve and said lock for preventing the opening of the door in the end of the chamber when said conduit valve is not open.

8. In apparatus of the character described, the combination of a lethal chamber, a door at one end of said chamber, a ventilating hood extending outwardly over said door, a suction fan for exhausting the space beneath said hood, means for introducing a lethal gas into saidchamber, and an interlocking mechanism between said fan and said gas introducing means which prevents the introduction of gas 1 into said chamber when said fan is not oper' ating to exhaust the space beneath said hood.

9. In apparatus of the character described, a the combination of a lethal chamber, a door at one end of said chamber, a lock for maini j taining said door closed, means for introducing a lethal gas into said chamber, and an interlocking mechanism between said door 1 lock and said gas introducing means which prevents the introduction of gas into said 5 chamber when said lock is in its door releasing position.

MATTHEW McCURRIE. 

